1. Technical Field
The present invention relates to a printing control device which refers to a color conversion table, and a printing control method.
2. Related Art
An image formation device such as a printer or a host device such as a personal computer performs control to color-convert an input image with reference to a color conversion table, and to print the image after color conversion. The color conversion table specifies, for example, a correspondence relationship between an input coordinate value of a RGB (Red, Green, Blue) color system that depends on a monitor and an amount of use of an ink (coloring material) of CMYK (cyan, magenta, yellow, black) that is used in the printer. The color conversion table is used in color conversion of gray images in which input coordinate values of RGB are the same. In order to check a subtle color of a monochrome image, it is considered to test-print a monochrome image whose color is subtly changed.
The image formation system disclosed in JP-A-2012-918 is not intended to print a monochrome image, but accepts a setting of a plurality of test color conversion tables, prints a plurality of test output images by applying each of the test color conversion tables, and uses a selected test color conversion table as a regular version of a color conversion table. Therefore, the test color conversion table and the regular version of the color conversion table have the same number of grid points, and the same number of gradations of an output value to be stored.
In order to improve an image quality of a monochrome image, it is necessary to provide a color conversion table which has large number of grid points or large number of output gradations. On the other hand, when performing list printing on test images having a subtle difference in color, providing a color conversion table which has large number of grid points or large number of output gradations for each test image requires a very large memory size for control processing on the list printing.
The problem described above is present not only in a technology of color-converting an input image of a RGB color system into an image of a CMYK color system to print, but also in other various types of technologies.